1. Field of the Invention
The invention relates generally to an enclosed write protect device for computer data storage media.
2. Description of Prior Art
Disk write protect devices prevent the unintentional erasure or overwriting of remanent data previously recorded. Heretofore a glue tab was used for that purpose. It is placed over a notch on the disk jacket to mediate the sensing of write enable by the computer. This tab is not convenient to use and once in place it is difficult to remove. Therefore, other methods have been devised, for example as were cited in Fann Patent # 4,521,820 and Tarter Patent # 4,618,060.
However each of these other methods also have disadvantages as well. One disadvantage common to these other methods is a protrusion beyond the plane of the media jacket. This will interfere with equipment used in the test, duplication and also the certification of the media. Another disadvantage to devices disclosed in prior art is that they contain a lip. Any lip so contained by a write protect device would make the installation of said device into the disk jacket very difficult, via the jacket notch or via the jacket top flap before as well as after this top flap is sealed. Since disk testing requires that as many as 100 disks be loaded into a hopper attached to automatic handling equipment, any lips and protrusion from the jacket can get snagged during this testing as well as during end user handling. An additional undesirable feature of this prior art device is that in one form there is contained a break away part or a perforated section which later must be removed for usage. Which would require additional handling and extra effort on the part of the potential user of this prior art device.
A fault of one other prior art device is that it was designed for the mechanical sensor with an arm therefore its design did not take account the optical methods which use light or infrared to pass thru the write protect notch to detect the blocked condition required to inhibit the erase and write function.
For a write protect device to be commercially acceptable it must be simple to use, positive in its setting, low cost and not interfere with the present equipment used for manufacture or testing of media. Said device also must not present additional problems for the individual user.
This new device solves all these problems, because it is recessed and enclosed within the jacket, and its activation mechanism is not exposed.
Another important feature of this invention is that the material used for fabrication is the same as the jacket material, which solves other problems inherant in prior art. It is readily available at very low cost and being opaque makes it ideal to block optical sensors. It is also rigid enough to block the mechanical arm sensor used in previous disk drive designs. Therefore one device can meet all demands required without additional modification or cost. No device up until now had all the features herein described